Scraper



M. A. CLARK April 5, 1960 SCRAPER 3 Sheets-Sheet 1 Filed Sept. 2, 1958 INVENTOR. Mar/a2: .2. 674114 A ri l 5, 1.950

M. A. CLARK 2,931,111

SCRAPER Filed Sept. 2, 1958 3 Sheets-Sheet 3 22 i I V 23 36 as s7 14 a2 29 57 30 29 INVENTOR.

Marion A. Clark SQRAPER 7 Marion A. Clark, Tulare, Calif. Application September 2, 1958, Serial No. 758,493 1d Claims. (Cl. 37-4) This invention relates to an improved earth working scraper.

In particular the invention is directed to, and it is a major object to provide, a scraperof earth carrying type-which includes a novel, multiple apron unit Whichin combination with a connected rear endgateaccomplishes faster, more positive, and better controlled loading and unloading of the scraper; the apron unit being power actuated, whereby an efiective loading actionother than that caused by advance of the scraper is attained, and unloading is performed with ease and close regulation.

Another important object of the invention is to provide a carry-type scraper which is operative, through the medium of such apron unit, to self-load a larger and more compact load than otherwise possible.

An additional object of the invention is to provide a carry-type scraper, as above, in which the apron unit includes a plurality of transversely extending, longitudinally spaced aprons connected together in unitary relation for powered movement-in st1ccession-into or out of the bowl from the front thereof during, and as an aid to, loading or unloading operations, respectively.

A further object of the invention is to provide a carrytype scraper wherein the aprons are connected in hinged or pivotally linked relation, and when out of the front end of the scraper bowl and in a forward, non-working position are upswung so as to be out of way of earth flowing into or from the scraper bowl with continuance of the loading or unloading operations; there being novel 1 mechanism to power advance or retract the apron unit, and to so upswing the aprons which are in said forward and non-working position.

A still further object of the invention is to provide a carry-type scraper which is useful not only for bulk transport of earth from point to point, but also for grading or leveling, and which requires closely controlled movement of the earth into and from the scraper bowl.

It is also an object of the invention to provide a carrytype scraper designed for ready and economical manufacture; simplicity of operation; and long service with a minimum of maintenance or repair being required.

Another object of the invention is to provide a practical, reliable, and durable scraper, and one which will be exceedingly effective for the purpose for which it is designed.

These objects are accomplished by means of such structure and relative arrangement of parts as will fully appear by a perusal of the following specification and claims.

7 In the drawings:

Fig. 1 is a side elevation of the scraper, showing the parts in the positions occupied thereby at the start'of a loading operation; the rear endgate being advanced, and the articulated multiple apron unit being raised.

Fig. 2 is a longitudinal sectional elevation of the scraper, showing the parts in'the positions occupied thereby when the scraper is fully loaded; the rear endgate being in its 2,931,111 S i Patented Apr. 5, 198i) Referring now more particularly to thedrawings, and

to the characters of reference marked thereon, the scraper comprises an elongated rectangular bowl, indicated generally at 1, and which is open at the top and front. Such bowl 1 includes a bottom 2 and sides 3; the bottom-at its forward edgebeing fitted with a transversely extending, forwardly and downwardly inclined digging blade 4.

The sides 3 of the bowl 1 each include an upper longitudinal side beam 5 and a lower longitudinal side beam 6. The lower side beams 6 project rearwardly of the bowl 1, and are there fitted with the transversely spaced rear wheels '7 of the scraper.

A draft yoke, of U-shape in plan, is indicated generally at 8; such draft yoke straddling the bowl 1 from the front thereof. The draft yoke 8 includes side arms 9 pivoted, as at it), to the lower side beams 6 intermediate the ends thereof, and said side arms are connectedat the front endsby a cross beam 11. The draft yoke 8 is supportedat the front, and centrally of its sidesby a caster-type wheel truck 12 having a forwardly projecting draft tongue 13 adapted for coupling to a tractor.

At the front end thereof each of the upper side beams 5 is formed with a rigid, upstanding end disc 14 of substantial diameter, and whose essential purpose will hereinafter appear; such end discs 14- facing each other in axial alinement.

A hydraulic power cylinder 15 is pivotally connected between each side arm 9, intermediate its ends, and the related end disc 14 adjacent the front thereof. Such power cylinders l5which are valve-controlled from the tractor in a conventional manner-serve to raise or lower the bowl 1 at its forward end, and thereby to regulate the position of the digging blade 4 relative to the earth.

An upstanding, transversely extending, rear endgate ld is disposed in the bowl 1, and such rear endgate which is forwardly concave-is fixed at its ends to vertical, laterally facing side skirts 17 which project ahead of said rear endgate. Additionally, the side skirts 17 include rearwardly projecting upper portions in the form of ears 18 to which laterally outwardly projecting rollers l9rare journaled.

The upper longitudinal-side beams 5 are of laterally inwardly opening channel form, whereby to define paral-. lel, straight-line guide channels 21) extending the full length of the scraper bowl 1. The rollers '19 of the rear endgate 16 ride in the guide channels 20.

. With reference to the scraper when all of the parts are in the positions occupied thereby when the scraper is fully loaded, the rear endgate 16 then occupies its rearrnos-t position, and ahead of such rear endgate and within the bowl 1 there is an articulated multiple apron unit, indicated generally at 21. Such apron unit comprises a plurality (here three) of upstanding, transversely extending, longitudinally spaced aprons 22; the rearrnost one of said aprons being a distance ahead of the rear endgate 16, while the foremost one of said aprons occupies a position in the front of said bowl 1 closely adjacent, but slightly rearwardly of, the digging blade 4.

The aprons 22 are rigidly attached at each end to a vertical, laterally facing side skirt 23. The side skirts 23 of the rearmost apron 22 extend rearwardly in lapping relation to the side skirts 17 of the rear end-gate l6 and adjacent the top of said lapping skirts the same are pivotally connected, as at 24; the pivots carrying laterally outwardly projecting rollers 25 which ride in the adjacent guide channels 20.

Forwardly of the rearmost apron 22 all of the side skirts 23 lap each other and are likewise pivoted together at the top by pivots 26 which carry laterally outwardly projecting rollers 27 also riding in the adjacent guide channels 20.

The side skirts 23 of the foremost apron 22 are fitted at their front upper cornerswith laterally outwardly projecting rollers 28 riding in the front portion of said guide channels 20.

All of the rollers are preferably of the type which include anti-friction bearings.

With the above described arrangement it will be apparent that the rear endgate l6 and the aprons 22 are connected together for movement in unitary relation; such movement being accomplished by the following mechanism:

Alined trunnions 29 are fixed centrally on and project inwardly from the end discs 14; the axis of such trunnions thus extending horizontally and transversely of the scraper above and slightly ahead of the front end of the bowl 1.

A tubular rotary cross shaft 30 spans between and turnably engages on the trunnions 29, and circular heads 31 are keyed onto the rotary cross shaft 30 adjacent the end discs 14. The circular heads 31 include reduceddiameter, integral sheaves 32 which project axially toward said end discs 14; such sheaves being multiple grooved The upper longitudinal side beams 5, which define the guide channels 20, each include a top flange 33 and a bottom flange 33a; the top flanges 33 terminating at their front ends substantially tangent to the related circular heads 31 at the bot-tom thereof. At the forward end each bottom flange 33a merges with the adjacent end of an arcuate guide flange 34 on the periphery of the corresponding end disc 14. Each such guide flange 34 projects laterally inwardly from the related disc 14 in spaced but concentric relation to the adjacent circular head 31, whereby to define an arcuate guide channel 35 communicating with-and forming an extension ofthe corresponding guide channel 20.

' Each guide flange 34 is spaced from the related circular head 31 a distance substantially the same as the depth of the corresponding guide channel 20, whereby the guide channels 35 may freely receive rollers from said guide channels 20. p The guide flange 34 on each end disc 14 extends over the top thereof but then terminates a substantial distance above the top of the bowl 1 so as to not obstruct the passage to the sheaves 32 of a cable system hereinafter described.

Links 36, carried on the pivots of the rollers 28, extend from the upper front corner of the foremost side skirts 23 to'pivotal connection, as at 37, with the circular heads 31; such links providing the operative connection between said circular heads 31 and the apron unit.

The circular heads 31 are simultaneously and reversibly rotated as follows:

A longitudinally extending, double-acting, hydraulic power cylinder 38 is disposed above-and mounted in rigid connection witheach upper side beam at the rear portion thereof; each such cylinder 38 including a forwardly projecting piston rod 39 fitted at the outer end with a cross head 40.

A lower cable 41 leads forwardly from the cross head 40 to the corresponding sheave 32, turning about the latter from the bottom and thence being anchored thereto. A pair of cables 42 extend in transversely spaced relation rearwardly from the cross head 40 and turn about sheaves 43 on a bracket 44 at the rear end of each cylinder 38. From the sheaves 43 the cables 42 extend forwardly to connection with a cross head 45.

An upper cable46 leads forwardly from thecross head 45 to the corresponding sheave 32, turning about the latter from the top and thence being anchored thereto.

With the above arrangement the lower cables 41 and the upper cables 46 are simultaneously and reversibly actuated upon operation of the power cylinders 38 in one direction or the other, which results in reversible rotation of the circular heads 31.

In operation of the above described scraper-and starting with the rear endgate 16, as Well as the aprons 22, all within the confines of the bowl 1--the power cylinders 38, which are simultaneously valve-controlled from the tractor in a conventional manner, are operated to cause advance of the piston rods 39. When this occurs, and through the medium of the described cable and sheave system, the circular heads 31 are rotated in a direction to cause said heads to turn upwardly at the front. Upon such occurrence the links 36traveling with the circular heads 3ldraw the articulated multiple apron unit 21 out of the bowl, and at which time the aprons 22 are caused to successively rise as the rollers 28 and 27 move out of the guide channels 20 and enter and move upwardly in the guide channels 35.

With the articulated multiple apron unit 21 in its upswung or raised position, as in Fig. l, the rear endgate 16 is disposed at the front of the bowl 1 adjacent the digging blade 4.

The scraper is then ready to load, and this is accomplished by first lowering the digging blade-by the power cylinders 15-into earth engagement. Thereafter, as the scraper advances and earth begins to flow into the bowl over the digging blade 4, the articulated multiple apron unit 21 comes into play. The power cylinders 38 are simultaneously actuated to retract the piston rods 39, and such movement-through the cable system-imparts rotation to the circular heads 31 in a direction so that the aprons 22, under the thrust of links 36 and as guided by the rollers in the guide channels, are successively returned to a position at the front of the bowl 1 and thence enter and move rearwardly therein.

As each apron 22 approaches and enters the bowl it produces a positive earth loading action, independent of the loading force from forward movement of the scraper, whereby a larger-and more compact load is accumulated in the bowl, and with greater ease and better control than heretofore possible. Further, as the load in the bowl is in separate, substantially filled pockets or compartments, center heaping is avoided and a more even load is obtained.

Additionally, each such pocket or compartment-- 'whether between the rear endgate 16 and the adjacent apron 22, or between aprons ahead thereofis, when the bowl is loaded, closed by the side skirts; this effectively confining the load against side spillage.

Also, as adjacent side skirts are to a certain extent lapped when adjacent but slightly ahead of the digging blade 4, transverse spillageduring loading of earth into the bowlis minimized.

To unload the bowl, the apron unit 21-together with the connected rear endgate 16is run forwardly, and with such movement the earth discharges from the bowl and is spread by the blade 4 as each pocket or compartment opens above such blade. In this manner, and as the extent of advancing movement of the apron unit 21 can be regulated by the operator, the earth-as discharged from the bowlcan be nicely controlled; this being of especial advantage when the scraper is used for leveling of land. Also, resistance to unloading is reduced, as the portions of the load in the pockets or compartments are separatelyalthough simultaneously-pushed ahead, in the bowl, to the point of discharge.

From the foregoing description it will be readily seen that there has been produced such a device as will substantially fulfill the objects of the invention, as set forth herein.

While this specification sets forth in detail the present and preferred construction of the device, still in practice such deviations from such detail may be resorted to as V l e l 7 do not form a departure from the spirit of the invention, as defined by the appended claims.

Having thus described the invention, the following 1s claimed as new and useful, and upon which Letters movement in the bowl between a retracted position in the bowl and an advanced position therein adjacent the digging blade; a longitudinally extending multiple apron unit ahead of the rear endgate and spaced therefrom, the apron unit including a plurality of upstanding transversely disposed aprons in longitudinally spaced relation,

means mounting the apron unit for movement between a.

having a bottom and sides, a digging blade on the front edge of the bottom, an upstanding transversely disposed rear endgate, and means mounting the rear end end-gate for movement in the bowl between a retracted position in the bowl and an advanced position therein adjacent the digging blade; a longitudinally extending multiple apron unit ahead of the rear endgate and spacedtherefrom, the apron unit including a plurality of upstanding transversely disposed aprons in longitudinally spaced relation, means mounting the apron unit for movement between a retracted position in the bowl and an advanced position out of the front end thereof, reversible power means connected to the apron unit operative to impart advancing or retracting movement thereto, selectively, and means connecting the apron unit to the rear endgate whereby the latter moves with said apron unit.

3. A scraper, as in claim 1, in which the apron unit is articulated for relative vertical swinging of said aprons, and guide means on the bowl cooperating with the apron unit to cause the aprons to swing upward or downward, in succession, as said unit advances and moves out of the bowl, or retracts and moves into the bowl, respectively.

4. In a carry-type scraper which includes a bowl open at the front and having a bottom and sides, and a digging blade on the front edge of the bottom; a longitudinally extending multiple apron unit disposed in the bowl, said apron unit being articulated and including a plurality of longitudinally spaced aprons connected together for relative vertical swinging movement, a transverse axis rotary structure journaled horizontally on the bowl above the front thereof, means pivotally connecting the apron unit at the front to said rotary structure, the apron unit being advanced out of the bowl and engaged in rolled-up relation on said structure with the aprons in substantially radial relation to the axis of the structure upon rotation of the latter in one direction and unrolled and retracted into the bowl upon rotation of such structure in the opposite direction whereby the aprons are successively swung upward and downward, respectively, relative'to the digging blade, and power mechanism operative to reversibly rotate said structure.

5. In a carry-type scraper which includes a bowl open at the front and having a bottom and sides, and a digging blade on the front edge of the bottom; a longitudinally extending multiple apron unit disposed in the bowl, said apron unit being articulated and including a plurality of longitudinally spaced aprons connected together for relative vertical swinging movement, a transverse axis rotary structure journaled horizontally on the bowl above the front thereof, means pivotally connecting the apron unit at the front to said rotary structure, the apron unit being advanced out of the bowl and engaged in rolled-up re- 6 la'tion on said structure upon rotation of the latter in one direction and unrolled and retracted into the bowl upon rotation of such structure in the opposite direction where- 'by the aprons are successively swung upward and downward, respectively, relative to the digging blade, and power mechanism operative to reversibly rotate said structure; said rotary structure including transversely spaced circular heads journaled on the bowl in facing coaxial relation, longitudinally spaced rollers projecting laterally outwardly from the sides of the apron unit adjacent the upper edges thereof, each circular head and the corresponding rollers being in the same longitudinal vertical plane whereby the rollers engage and ride on said heads upon said roll-up or unrolling of the apron unit.

6. A scraper, as in claim 5, in which said power mechanism comprises a sheave on each circular head, a double acting powercylinder mounted lengthwise on the upper edge of each side of the bowl rearwardly of the corresponding sheave, and cable systems connected between the power cylinders and the corresponding sheaves operative to translate action of said cylinders into rotation of the sheaves.

7. A scraper, as in claim 5, including a rear endgate in the bowl spaced back of the apron unit, and means connecting the rear endgate to the apron unit for movement therewith; the rear endgate being disposed adjacent the digging blade when the apron unit is advanced out of the bowl and in rolled-up relation on the rotary structure.

wardly opening parallel guide channels on the sides of the bowl, the rollers engaging in. said guide channels when the apron unit is in said bowl, the guide channels each including a top flange having its forward end substantially tangent to the corresponding circular head at the bottom thereof.

9. A scraper, as in claim 8, in which the guide channels each include a bottom flange, the latter being extended beyond the front end of the bowl and part-way about the corresponding circular head in concentric but spaced relation thereto whereby to define with said head an arcuate guide channel for reception of the related rollers upon said roll-up or unrolling of the apron unit.

10. In a carry-type scraper which includes a bowl open at the front and having a bottom and sides, and a digging blade on the front edge of the bottom; parallel, laterally inwardly opening guide channels on the sides of the bowl adjacent the upper edge thereof, arcuate extensions of said guide channels projecting upwardly from the front of the bowl, a multiple apron unit in the bowl between said guide channels, the apron unit including a plurality of longitudinally spaced aprons and'being articulated for relative vertical swinging of said aprons, longitudinally spaced laterally outwardly projecting rollers on opposite sides of the apron unit, said rollers being engaged in corresponding guide channels, and reversible power mechanism operative to advance the apron unit out of the front of the bowl and to then retract the apron unit into the bowl; the rollers successively engaging in the extension guide channels, and the aprons swinging up, and the rollers successively disengaging from the extension guide channels and theapronsswinging down, upon said advance or retraction, respectively, of the apron unit.

11. In acarry-type scraper which includes a bowl open at the front and having a bottom and sides, and a digging blade-on the front edge of the bottom; parallel, laterally inwardly opening guide channels on the sides of the bowl adjacent the upper edge thereof,.arcuate extensions of said guide channels projecting upwardly from the front of the bowl, a multiple apron unit in the bowl between said guide channels, the apron unit including a plurality of longitudinally spaced aprons and being articulated for relative vertical swinging of said aprons,

' longitudinally spaced laterally outwardly projecting rollers on opposite sides of the apron unit, said rollers being engaged in corresponding guide channels, and reversible power mechanism operative to advance the apron unit out of the front of the bowl and to then retract the apron unit into the bowl; the rollers successively engaging in the extension guide channels, and the aprons swinging up, and the rollers successively disengaging from the extension guide channels and the aprons swinging down, upon said advance or retraction, respectively, of the apron unit; the articulated apron unit including a laterally facing side skirt fixed to the ends of each apron, adjacent side skirts extending toward and lapping each other, pivotal connections between lapping side skirts adjacent the upper edge thereof, and certain of the rollers corresponding to and being mounted on the pivotal connections; 7 v

12. In a carry-type scraper which embodies a bowl having a bottom provided at the front end with a digging blade; an apron unit comprising a plurality of longi ttudinally spaced aprons, side members rigid with the aprons,-a pair of longitudinally spaced rollers mounted on each side plate, pivot connections between adjacent rollers of adjacent aprons whereby the apron unit is articulated, guide tracks for the rollers each extending lengthwise of and parallel to the bottom of the bowl and then extending above the front of the bowl as a circular portion of suflicient circumferential extent to receive the rollers of all the aprons, and means to reversibly move the apron unit along the tracks.

13. A scraper, as in claim 12, with a rear endgate in the 'bowl guided for movement lengthwise of the portion of the track parallel to the bottom of the bowl and con nected to the rearmost apron for movement therewith; .said endgate being at the front end of the bowl when the References Cited in the file of this patent UNITED STATES PATENTS 1,891,266 LeTourneau Dec. 20, 1932 2,396,289 Robb Mar. 12, 1946 2,454,101 Snead Nov. 16, 1948 2,565,384 Lindquist Aug. 21, 1951 2,573,720 Lichtenberg Nov. 6, 1951 2,844,892 Carston July 29, 1958 Mt Am 

